Support Custom Samplers

[forestsword]

Component(s)

auto-instrumentation

Describe the issue you're reporting

Hello, I'd like to be able to use a custom sampler that I'm injecting as an extension for Java applications. However the sampler type in the instrumentation is an enumeration and I cannot configure it to use my sampler. I don't suggest to remove the type check but there should be some escape hatch to be able to do this.

Could a custom sampler type be added to the list and add a 3rd field like sampler.custom_type that takes any string but is only used in combination with the custom sampler?

I also just noticed the Java sdk is even including new samplers that are not in the type check: https://opentelemetry.io/docs/languages/java/sdk/#sampler

Thanks

[pavolloffay]

Did you try defining the sampler env variable in the instrumentation CR as a workaround?

[pavolloffay]

I am also not opposed for adding a custom sampler type to the instrumentation API